Justice Department Says No Thanks to Forensic Science Report

Common crime lab techniques made famous by shows like Law & Order have come under fire yet again—this time by President Obama’s top scientific advisers. A damning report released this week by the President’s Council of Advisors on Science and Technology calls into question the scientific basis of the forensic analysis of bite marks, mixed DNA samples, hair samples, and footwear, among other techniques. In spite of the esteemed origin of the report, Attorney General Loretta Lynch said the Justice Department wouldn’t heed the findings.

“While we appreciate their contribution to the field of scientific inquiry, the department will not be adopting the recommendations related to the admissibility of forensic science evidence,” Lynch said in a statement.

The brush-off from the nation’s top cop might come as a surprise, but it’s worth noting that prosecutors have relied on evidence garnered by these techniques to win cases for decades. The FBI was also quick to release a statement asserting that the report made many “unsupported assertions” about forensic science. If a growing list of widely accepted forensic analysis techniques is called into question—as it just was—what does that leave prosecutors?

“Juries are unschooled in forensic science and tend to believe the prosecutor’s expert testimony,” Nancy Petro, coauthor of False Justice: Eight Myths That Convict the Innocent, told TakePart. “While the defense’s cross-examination is meant to challenge this testimony, often the defense lacks the resources to do so effectively.”

Petro credits the denial of PCAST’s research to a “tough-on-crime” culture that “reinforces the notion that prosecutors are most successful when they get a conviction.”

Mississippi-based forensic dentist Michael West is among the analysts who have hesitated to embrace findings that question their tactics. West has contributed bite-mark-analysis testimony in nine states across three decades. He is frustrated by reports like that from PCAST.

“Forensic science is science,” West told TakePart. “This is simple wound-pattern analysis; it’s a yes-or-no kind of question. If you don’t have the rules of evidence, you’ve just got anarchy.”

The National District Attorneys Association also dismissed PCAST’s findings, calling them “scientifically irresponsible” in a statement and noted, “Adopting any of their recommendations would have a devastating effect on the ability of law enforcement, prosecutors and the defense bar to fully investigate their cases, exclude innocent suspects, implicate the guilty, and achieve true justice at trial.”

Like all evidence, the NDAA’s statement argued, forensic analysis is subject to cross-examination and evaluation in courtrooms, which is where the group would like the scrutiny of evidence to stay. In spite of this resistance, PCAST’s report is not the first time experts have challenged common forensic methods. In April, the FBI released a report admitting that microscopic hair analysis used in 95 percent of its criminal cases over two decades was flawed. Other forensic methods, such as tire-tread and shoe-print analysis and gunshot residue swabbing, were challenged in a 2009 report from the National Academy of Sciences. While that report recommended the creation of a federal body that would oversee and routinely certify forensic sciences, no such agency exists.